In optical communication that can transmit optical information obtained by photo-electrically converting large-volume digital information at a high speed by using an optical fiber, an optical communication module is used for optically coupling the optical fiber with a photoelectric conversion element of either one of a light emitting element and a light receiving element fitted in a photoelectric conversion element package.
As this type of optical communication module (optical fiber module), various structural forms have been developed. As a conventional example, there is an optical fiber module including a light emitting device (or a light receiving device) and a housing (for example, see Patent Citation 1).
FIG. 1 is a longitudinal sectional view showing a conventional optical fiber module.
The conventional optical fiber module 100 shown in FIG. 1 is disclosed in Patent Citation 1 mentioned above, and is explained briefly with reference to Patent Citation 1.
As shown in FIG. 1, the conventional optical fiber module 100 includes a light emitting device (or a light receiving device) 110 in which a light emitting element (or a light receiving element) 112 and a light emitting IC (or a light receiving IC) 113 are fitted to one side 111a of a substrate 111, and a housing 120 coupled with an optical fiber (not shown) and mounted on the one side 111a of the substrate 111.
In the light emitting device 110, an LED (Light Emitting Diode) or the like is used as the light emitting element 112. On the other hand, a PD (Photo Diode) or the like is used as the light receiving element 112, and either one of the light emitting element 112 or the light receiving element 112 is fitted to the substrate 111.
In the housing 120, a cylindrical sleeve 120a having a light transmission hole 120a1 formed therein for inserting/deinserting the optical fiber (not shown) and a square body 120b having a stepped depression 120b1 formed therein for housing the light emitting device (or the light receiving device) 110 are connected with each other and integrally formed.
A sealing resin 121 for sealing the light emitting element (or the light receiving element) 112 and the light emitting IC (or the light receiving IC) 113 attached to the substrate 111 is filled in the depression 120b1 in the body 120b of the housing 120, and a transparent epoxy resin or the like is used for the sealing resin 121.
It is described that when the light emitting device (or the light receiving device) 110 is housed in the depression 120b1 in the body 120b of the housing 120, hooks 120b2 formed on side walls opposite to each other in the body 120b are engaged with notches 111b1 formed on upper and lower parts of the other side 111b opposite to the one side 111a of the substrate 111, so that the light emitting element (or the light receiving element) 112 fitted to the substrate 111 has the same optical axis K as that of the light transmission hole 120a1 formed in the sleeve 120a of the housing 120, thereby enabling to reduce the number of man-hours for assembling the optical fiber module 100 and reduce the cost thereof.    Patent Citation 1: Japanese Patent Application Laid-open No. 2006-30813